Shipping Carrier and Method not Available on Leads and Prospect Record

Estimates from Lead and Prospects records will use the Default Shipping set under Set Up > Accounting > Shipping.

Lead and Prospect records do not have Shipping Carrier and Shipping Method because they do not guarantee sales transactions. There is no need for these records to have default values for these fields.

Customer records have Shipping Carrier and Shipping Method because of an existing or the likelihood of future sales transaction.

Note: There is an Enhancement request filed 129481 - List > Relationship > Leads/Prospects > Financial tab > Expose Shipping item field on a lead/prospect status forms, just like its available on a Customer form.